Telegraphic printing system and method



Nov. 28, 1950 J. J. ACKELL ET AL TELEGRAPHIC PRINTING SYSTEM AND METHOD 6 Sheets-Sheet 1 Filed Dec. 22, 1945' INVENTORS Nov. 28, 1950 J. J. ACKELL ET AL 2,531,358

' TELEGRAPHIC PRINTING SYSTEM AND METHOD Filed Dec. 22, 1945 6 Sheets-Sheet 2 AT 7 61 3 21? Y Nov. 28, 1950 Filed Dec. 22, 1945 J. J. ACKELL ET AL 2,531,868

TELEGRAPHIC PRINTING SYSTEM AND METHOD 6 Sheets-Sheet 3 INVENTORS .m Q I Z OWN l $%w SN @NW J J ACKELL ET AL TELEGRAPHIC PRINTING SYSTEM AND METHOD Nov. 28, 1950 Filed Dec.

Nov. 28, 1950 J. J. ACKELL ET AL TELEGRAPHIC PRINTING SYSTEM AND METHOD 6 Sheets-Sheet 6 Filed Dec. 22, 1945 NNINJH. W\Q.DM. QWMN' SE eh M? q a mum. Wbm 1 \Y M i Raw, 1 H u 3% w? //Nwm, mww 9mm. wmw O O M nwm. M wmm K SQ QR w wwm J Rum m md Q? A Wm Aw b\m.1\ NNN Mu. MN M M wmmd\\ %Nw Wm \ww www @MW W AYTUfF/SZE' Patented Nov. 28, 1950 srmss mrsm orrics ware Appiication December 22, 1945; Serial No. 636,588

(0!. its- 4) 12 Claims. 1

This invention relates to an improved system for transmitting, receiving and interpreting telegraphic signals by which messages may be printed on Siiitabl apparatus under remote control. It has particular referenc to the control of telegraphi page printer's auhough ertain featu'res or the invention ar applicable to tape primers. h v

A primar object or the inv ntion has been to speed the operation of telegraphic printing systems in which the selection of a character to be printed, or of some" other function of the printer, is effected 65; the ste -by-step rotation of a printing wheel. Toward this end the inventiori ete'mpiats the steio-by-steb advance of the printing wheel two characters at a time, provision bingmade for the selection of the desired one of two adjacent characters on the h t a While the present invention is adaptable for a wide variety of uses it is particularly intended for use in connection with a system in which signals in the form oi electrical pulses are sent out over a plurality of transmission lines to a large number of printing units at outlying points which are, for example, in the hands of subscribers, at those points, to the news or stock quotation service, or the like, with which the system is identified. The transmitted signal or series of pulses may, for example, be sent out by a transmitter which is under control of a punched tape, this tape having been punched in accordance with the characters to be printed, or other functions to be performed, at the outlying points. such a system the control tape may be perforated by means of manually controlled punching devices, Several operators may be engagd in this work and then a single transmitter may be liSd to send the signals determined by the several tapes, In transmitting a message the appropr t'e series 'of pulses will be sent out overthe lines t6 caiise the printing wheels to 'i te step by step to' the successively selected position According t'ci the present invention the signals of pulses which cause the Sizep-by-stp rotation of the printing wlieels are alternately positive and negative pulses The printing operation is controlled b'y a signal of somewhat greater duration than the regular pulsing signals. In one embodiment of the invention the printing is controlled by an opensignal of predetermined duraash an a distinction is drawn between two difr'erent types of printing operation according to the length of this open signal. Thus the type wheel is rotated step by step two character spaces at a time, by alternate positive and negative pulses, and then it one of two adjacent characters is to be printed a relatively short open signal will be transmitted to cause the printing while if the other of the two characters is to be printed an open signal of longer duration will be sent and this will bring about a slight rotation of the printing wheel,- to the extent of one character, before the platen is operated to effect printing.

It is thus a broad feature of the invention to provide a commutator and suitable electrical circuits operable in conjunction therewith to transmit current signals for the operation of escapement mechanism to effect a partial se lection of a character and to transmit a signal of diiferent character to complete the selection.

A special feature of the invention, which enables the use of the positive, negative and open signals of difierent duration for controlling the various functions of the printer; is the use of a rectifier in combination with a relay to differentiate between the various signals.

Another feature of the invention is the provision of suitable circuits and devices by which the remote printer may be set into operation by the simple sending out of a current signal and the printer may be thrown out of operation by the opening of the transmitting circuit for a predetermined of time.

fitill another feature of the invention is the ut itation of open signals at varying duration t 'o' perform a wide variety of different functions 'Ifhii's, in the preferred embodiment of the invention relatively short open signals of different duration will complete the selection of the char acter to be printed. An open signal of somewhat longer duration will cause the rin ing of a bell in the printer andan open of still longer duration will cause the printer to be thrown out of operation. h

h A further feature of the invention in its preferred form is the arrangement of the characters on the printing wheel in such a way that those most frequently used are arranged alternately around the wheel and in positions requiring the least to be done in effecting a printing operation. Thus, in the one embodiment the ar-- rangement is such that the characters most 'frequently used are printed without the necessity of a one-step backward turn of the wheel. The remaining characters are interspersed with these and require the turn-back operation. In so far as compatible with the foregoing the characters are arranged with regard to frequency of occurrence in sequences.

In connection with the foregoing it is a further feature of the invention to provide means at the transmitter for adapting the conventional five-hole punched tape, with its customary relation between the tape openings and the characters selected, to the selection of the characters in their new arrangement around the printing wheel.

Other objects, features and advantages of the invention will appear from a detailed description of several illustrative forms of the invention which will now be given in conjunction with the accompanying drawings, in which:

Figs. 1 and 2 in combination, with Fig. 1 above Fig. 2, disclose schematically devices at both the transmitting and receiving ends of a printing telegraph system embodying certain features of the invention;

Figs. 3a and 3b placed side by side with Fig. 3a at the left of Fig. 3b, disclose schematically the circuits involved in a more complicated modifled form of transmitter embodying the invention;

Figs. 4a and 4b are current flow diagrams indicating the character and duration of the current flow through the coil of the escapement magnet of the system disclosed in Figs. 1 and 2 under certain assumed conditions;

Fig. 5 is a similar current flow diagram showing the character and duration of the current flowing through the signal transmitting lines of the system disclosed in Figs. 3a and 3b; and

Fig. 6 is a diagrammatic view of the circuits in a printer adapted to be controlled by the transmission system illustrated in Figs. 3a and 3b.

Turning now to Fig. 2, the system illustrated is of a relatively simple type adapted for manual control by keys ll] cooperating with helically arranged pins or stops l I on a drum H which is arranged to be driven in a counterclockwise direction, as indicated by the arrow I3. A friction clutch is provided in the drive between a motor (not shown) and the drum E2, to permit slippage of the drive whenever the drum is arrested by a depressed key. 7

The parts are illustrated in Figs. 1 and 2 in the position they will assume after the letter V has been printed. Assuming now that it is desired to print the letter M, the M key will be depressed and this will automatically release the previously depressed V key, in a manner known in the art. The cylinder I2 will begin to turn and will rotate until stopped by the cooperation of the selected pin ll with the M key. In the rotation of the drum l2, a commutator I4, which is connected to turn with the drum, will rotate to carry several of its sections past a group of brushes l5, l6, and [1. On the first step of movement from V to H a current will pass between the brushes l5 and H. This current may be traced from the positive side of a generator [8 through brush ll, through the commutator segment in line with the letter H, thence through brush l6, partly through a line 9 to and through a relay 2t, and then back through a line 2| to the negative side of the generator It]. For a reason to be explained hereinafter, the relay 2! is of aslow acting type and will not operate to pull-up on its armature 20a in response to the brief flow of current just mentionecl, assuming that the commutator continues to rotate until an insulating section is brought opposite the brushes and thus breaks the flow of current just described. Another branch of the circuit through the brushes i6 and H, as described above, will pass through a line 22, through an armature 23 of a relay 2d, thence through a line 25 to and through the coil of a pulsing magnet 26 (Fig. 1) which operates an escapement 21 associated with an escapement wheel 28. The latter is carried by a printer shaft 29 on which is mounted a type wheel 29a whose position corresponds at all times with the position of the commutator I l. From the pulsing magnet 26 the circuit passes through a line 30 to a rectifier 3| in which the current is directed as indicated by the arrow 32 to the point 33, thence through the coil of a relay back through a line 35, and through a branch 36 of the rectifier to a line ill from which the current returns to the negative side of the generator. Flow of the current through this second branch of the circuit not only serves to pulse the escapement 2?, 28 one step, but also serves to pull-up on an armature 38, because of the passage of the current through coil 3 5. As a result of this action on armature 38, current from a source 39 will flow through a line at to and through the coils of a printing magnet 4i and back through a line 52 and armature 38 to the source. Operation of the printing magnet will release the printing shaft 43 and permit it to be rotated slightly until a projection 24 on an escapement disc is brought against the lower tooth of a printing-control escapement pawl G5. As the shaft 53 turns in the manner indicated, driven through a suitable friction clutch, by a motor not shown, in a manner well known, a cam disc 46 has its high portion carried away from the end El of a pawl 58 and thus permits this pawl to rock in a clockwise direction to retract a pawl 49 in preparation for a possible one step return movement of the shaft 29, in a manner to be explained hereinafter.

Simultaneously with the energization of the printing magnet it, current from the source 39 will also flow through a magnet coil 5t thus pulling-up on an armature 5! and rocking the pawl 39 in a counterclockwise direction to carry its active tooth 52 out of engagement with a ratchet wheel 53 on the printing wheel shaft 29. Magnet as is operative in this manner throughout the pulsing operations of the magnet 25. This is necessary to enable the step-by-step movement of the printing wheel shaft in response to the pulsing operations of the escapement 21, 28.

It should be noted at this point that so long as the commutator is is rotating from one position to the next, current will flow through the relay 3 t in the manner explained to pull-up on the armature 38 and permit current from the source 39 to pass through both the printing magnet ill and the magnet 58', thus maintaining the parts in the position just described.

Returning now to the commutator, as the latter continues to rotate and carries the next position, designated K, in line with the brushes, no current will flow through the circuits including these brushes and, therefore, no pulsing operation will be imparted to the escapement 26. The pawl 2'! will remain in the position to which it was last shifted. Since the commutator continues its rotation at this time the open circuit created is very brief. For this purpose the insulating sections between the successive conducting sections of the commutator are very short, circumferential y, The interruption of the current flowing through the relay 34 will not be of sufficient duration. to release the armature 3 8 and hence current from. the source 3S will continue to flow through the printing magnet M and the magnet 5.0..

Upon the. continued rotation of the commutator the part opposite letter L will be brought in line with the brushes and current will flow between the brushes tand it. This current will flow from the positive side of the generator i800. through the line 3], through the rectifier in a clockwise direction to. the point 33., through the relay M back. through the line 3.2-3 to the rectifier, up tothe point 54. in the rectifier, through the line 33,, thence through the pulsing coil of the escapement 2.3 in the reverse direction from the preceding pulse, back through the line 25., armature 23., line 22, brush it, brush l5, and line 55 to the. negative side of the. generator Ma. The reverse flow of the current through the coil 26 in the manner explained, will cause the escape-- ment. pawl 2.! to. rock to the opposite side, thus permitting the escapement wheel 28. and shaft 29. to rotate through /20 of a revolution in the illustrative system in which wheel 28 has ten teeth. It should be noted, furthermore, that due to the action of the rectifier 3! the current flowing through the relay it is always in the same direction regardless of the fact that the current is reversed or alternated in its fiow through the lines 25, 36.! and 31.

As the commutator It now continues to rotate, the insulating section opposite the dollar sign is brought in line with the brushes and a temporary interruption of the current from the generators is and its is encountered. However, the situation is the same as explained above in connection with the insulating section K. Now as the commutator continues until the segment M is brought in line with the brushes, current will flow between the brushes i5 and ll in the same manner as explained in connection with section H of the commutator so that current will flow through the coil 26 of the escapeme-nt from the line 25 to the line 36, thereby shifting the escape ment pawl 21 to the other side and permitting another step of. rotation of the escapement wheel 28. Since we have assumed that the M key has been depressed, the cylinder i2 will now be arrested with the commutator segment M in line with the brushes, thus continuing the circuit through the brushes it, I! for a prolonged inter val. This interval will be suflicient to bring about operation of the slow relay as so that the armature 2iia of the latter is drawn up, thus permitting the flow of current from the positive side 5% of a current source through the relay 24, through a conductor 51 to contact 58, thence through armature Zlia to and through a condenser 59 down to the negative side 69 of the current source. This current, however, will have a suilicient amperage to retain the armature 23 toward the left for a. brief interval, i. e., a time sufficient to charge the condenser 59 to a predetermined extent. During this brief interval of current flow the relay 24 will have been energized and the armature 23 will have been pulled away from the contact 6: so that the current flowing through the line 25 to the pulsing coil 26 and also through the relay 34 will be temporarily interrupted, The interruption of flow through the coil 26 will simply serve to leave the escapement pawl 2'! in its last set position. Interruption of current flow through relay 34 will per mit the armature 38 to be released and will thus the left in Fig. 1.

interrupt the flowof current from the source 39 through the printing magnet 4| and through the magnet. 50. This interruption of current will, however, be relatively brief since. the condenser 59. will. be charged rather quickly and the current thenpermitted to flow through thecircuit from 5&- to $0 will be toosmall tohold armature 23. The interruption, however, is sufficient to permit. the. spring :52 associated with the printer escapement pawl to rock the latter in a clock wise direction, thus releasing the projection 44 from. the lower tooth of the pawl and permitting about 140 of revolution of the shaft 43, until projection 44 strikes the upper tooth of the pawl. During, this revolution of the shaft 43 various things identified with the printing operation are performed. Firstly, the cam 46 will act upon the pawl or lever 48 to rock the latter counterclockwise. and carry the pawl 4:9 longitudinally toward Magnet 50, however, will be energized at the time the pawl 49 is thus shifted because of the briefness of the interval of deenergization determined by the condenser 59. Therefore, the pawl 49 will be inefiective. and will not rotate. the ratchet wheel 53 and the printing wheel Zea will remain in the position determined by the escapement 21., 28. Rotation, of the shaft i3-wi1l also cause a cam 5&- to operate aprinti-ng; lever 55 and thus carry a platen 66 against the type of the wheel 29a which has been selected This will, in the assumed case, be the letter M. It will be understood, of course, that paper will be interposed between the platen andthe printing wheel at this time and it will also be under stood that the wheel is suitably inked in the course of its rotation, as by contact with an inked felt roller.

The printing wheel 29a is preferably shiftable axially of the shaft 29. For this purpose it is mounted upon a carriage (not shown) which may be similar to that shown in the Landfear Patent No. 265,978 granted July 26, 1904, and adapted to. be given a step-by-step movement across the page upon which the printing is being done. Upon completion of the printing of a line across the page, the carriage may be automatically restored to the opposite side and the operation repeated. In the simple. form of circuit illustrated in Figs. 1 and 2 no control is shown for x the operation of the carriage. either step-by-step or in its return movement toward the opposite side. However, it will be understood that any suitable arrangement may be employed for this purpose, such as the arrangements described hereinafter in connection with the more compl-icated circuits illustrated in Figs. 3 and 6.

Fig. 4a illustrates schematically the flow of current from the generators l8 and [8a through the. pulsing coil .26 and the rectifier 31 as well as through the parallel circuit of the relay 20. The line in this diagram indicates the control over the current from the generators i8 and lSa exercised by the commutator Hi in cooperation with the brushes 65, It, and H. In moving from the i position V to and beyond position H a positive current of a duration indicated by the length of the section 6'? will flow through the pulsing coil '26 and through the relay 253. The duration of this current, however, is not long enough to operate the relay 2%., which as indicated above is a slow acting relay. In passing from H to K the current will be interrupted through the pulsing coil, the rectifier, and the relay 20, as the. brush i6 strikes the insulating section at K, but this interruption is for a considerably briefer period than as last set.

the positive current flow indicated at H. When the segment L of the commutator reaches the brushes, a negative current will flow through the pulsing coil and through the relay 29, thus rocking the escapement pawl 21 in the opposite direction from that in which it was rocked by the current flowing at position H. Another brief interruption in the current occurs at the dollar sign position as the brush it passes over the insulating segment at this point and this is followed by a positive flow of current when the.

segment M is brought in line with the brushes. As schematically indicated by the line in Fig. 4a, the commutator predetermines a long period of positive current flow through the pulsing coil circuit as the drum is now brought to rest by the M key but due to the operation of the relays 2B and 24 at this time, the actual current flow through the pulsing coil 26 is modified to correspond with that indicated by the line in Fig. 41). Thus the temporary opening of the circuit between armature 23 and contact 6i, due to the attraction of armature 2 in and the resulting flow of current through relay 24 and condenser 59, will produce the interruption indicated at 63 in Fig. 41). As soon as armature T23 is released, however, the positive pulse will be restored, as indicated by the section 69 of the current flow line.

Let us assume now that the next character to be printed is the numeral 3. This, as will be seen, is the next position on the commutator to the letter M in which the parts are assumed to have been arrested. It will also be noted that this is opposite an insulating section so that depression of the 3 key will stop the drum l2 with an insulating section in engagement with the brush l6. Since the effect of moving from the conducting sector at M, which bridges the two brushes Hi and Il to the insulating section at 3, is simply to interrupt the flow of current through the pulsing magnet 26, the escapement pawl 27 will remain in its last set position and, therefore, the shaft 29 and printing wheel 2911 will remain It should be noted, moreover, that the interruption of the flow of current through the relay 20 at this time serves to release the armature 20a and thus breaks the circuit from 56 to 60 through the condenser 59 and permits this condenser to be discharged through the resistor "Hi. It may be noted at this point that the release of the armature 28a and the consequent discharge of the condenser 59 would have taken place even though no prolonged interruption of current flow had taken place at this particular instance. That is, if the commutator were permitted to rotate for some distance, so that a pulsing current would be permitted to flow through the relay 20, this would, nevertheless, release the armature Ziia and thus condition the condenser 59 for the next printing operation. Any reversal of flow of the current through the relay 20 will bring about such release of the armature.

It will be noted by reference to the diagram of Fig. 4b that at the conclusion of the printing operation for the letter M current will have been flowing through the relay 34, Whereas upon the operation of the 3 key and the turning of the cylinder E2 to this new position, the current flow through the relay 34 will be interrupted, this interruption being relatively long. The effect of this is to release the armature 38 and thus break the circuit through the print magnet 4| and the magnet 50 throughout the long interruption.

Upon de-energization of the print magnet 4|, spring t2 will rock the pawl 45 clockwise to release its lower tooth from the then engaged projection 44 and will permit the shaft 43 to rotate until this projection 44 is arrested by the upper tooth on the pawl. As in the previous printing operation, the cam 46 will operate the lever 48, rocking it in a counterclockwise direction to carry the pawl 49 toward the left and since, at this time, the magnet 55% will be de-energized the spring H will draw the armature 5| downwardly and rock the pawl 49 into engagement with the ratchet 53. The longitudinal movement of the pawl 49 will, therefore, turn the ratchet, and hence the shaft 29, through a step in a backward direction. This step is 4 of a revolution of the shaft in the construction illustrated. It is only one-half the movement given the shaft upon each operation of the escapement. In this connection it should be noted that ratchet 53 has 20 teeth, when ratchet 28 has 10 teeth. Thus at the time the cam 64 operates upon the printing lever to effect the printing operation, the wheel 29a will have been turned a step back from the position which it assumed upon the printing of the letter M. It will be noted, in this connection, that the arrangement of the characters on the printing wheel 297a differs from the arrangement of the corresponding positions on the commutator I l. Thus, whereas the figure 3 follows the letter M on the commutator, it must precede the letter M on the printing wheel.

Assuming now that the next character to be printed is the letter E, depression of the E key will permit the commutator to rotate one more step and will carry the conducting segment opposite E (Fig. 2) into line with the brushes to complete a circuit through the brushes l5 and I6. This causes a current to flow from the positive side or" the generator I to through line 31, through rectifier 3!, relay 34, and line 30 tothe pulsing magnet 26, then back through the line 25, armature 23, line 22, brush I6, contact segment E, brush l5, and line 55 to the negative side of the generator. The current in passing through the pulsing coil will cause the escapement pawl 21 to shift to the opposite side and permit another step of movement of the ratchet 28 and hence the printing wheel. It should be observed in this connection that each movement of the printing wheel, permitted by each step of movement of the ratchet 28, serves to carry two characters past the printing point. Thus a 10 toothed ratchet 28 may be stopped in any of 20 different positions by the pawl 21 and the printing wheel 63 may have as many as 40 characters or spaces around its periphery.

The current in flowing through the relay 34, as just explained, will serve to energize the print magnet 4i and the magnet 50, the latter being necessary to permit the rotation of the shaft 29 through. the one step indicated. By energizing the print magnet 4!, the shaft 43 is released for a partial movement of about 40 until the next tooth 44 engages the lower tooth on the pawl :25. This, as previously explained, is sumcient to cause rocking of the lever 43 in a clockwise direction, thus retracting the pawl 49 and making it ready for the next operation in the event that it is necessary to turn the printing wheel shaft 29 a half step backwardly in the manner explained. However, in printing the letter E the pawl 49 will not be rendered effective since the interruption of flow through the relay 34 will be e of the shorter type predetermined by the con-' alsa 9 denser 59. This fact is shown by the section I2 of the current new line in Fig. 41), this section being similar to the section designated 69.

The foregoing simple system serves to illustrate the principle of utilizing positive and negative pulses through the escapement coil 26 to bring about step by step movement of the type wheel and of utilizing a neutral signal, oran in terruption of current, to bring about a printing operation which may be of either of two types depending upon the length of the interruption. A short interruption will cause printing of the character selected by the escapement 2?; 23, whereas a long interruption will bring about the printing of the character just in advance of the one selected by the escapement 2?, 28. Thisis accomplished by the operation of pawl i'5i, which turns the printer wheel backwardly a half step upon a long interruption.

Figs. 3a and schematically a system of circuits forming part of a transmitter generally similar to that disclosed in the Ackell and Paulding Patent No. 2,017,087, granted October 15, 1935. The system disclosed. in Figs. 3a and 31), however, is adapted placed side by side, illustrate in any number of the five possible positions for analyzing device, including a series of 5 pins capable of cooperating with the various holes in the punched tape and various relays and circuits controlled by switches, operated in response to the action of the pins, and a commutator structure replace the pin cylinder 12 and the commutator l4.

As in the Fig. 2 embodiment, the signals sent out from the transmitter of Fig. 3 are of three different types, i. e., positive, negative, and open. The positive and negative signals are utilized to bring about the step by step pulsing operations of the printers at the outlying points, while the open signals are used for any one of five diiferent purposes. A short open signal will bring about a p'inting operation at the distant machines of a kind in which a character on the type wheel that is brought to the printing position by the normal pulsing operation of the escapement mechanism is printed. A longer open signal of say twice the duration of the short signal mentioned above, will bring about a printing operation in which the type wheel is turned a half step or character space backward from the position predetermined by the pulsing of the escapement mechanism, before the printing takes place. A still longer open signal, of say 3 or 4 times the duration of the second mentioned long open printing signal, will bring about the return of the carriages of the various outlying printers. A still longer open signal, of say about five times the duration of the carriage return signal, will bring about the ringing of a bell at each of the printers. Finally, an open signal of indefinite duration, i. e., of 4 or 5 minutes or more, will bring about the cutting off of power to all of the outlying printers.

The printers which are to be controlled by the signals sent out through the operation of the 10 transmitter illustrated in Figs. 3a and at, my suitablybe of the same construction as is diagrammatically illustrated in Fig. '1. So also, as

indicated by the foregoing, the manner of control of this printer is substantially the same as described in connection with Figs. 1 and 2. There "are, however, a few specific differences. For example, the Fig. 3 system has the ability to repeat the same character without causing any change in the position of the printing wheels of the printers, other than that which might be necessitated as a turnback in the printing operation. in the operation of the Figs. 1 and 2 construction, this was not possible since it was necessary on each operation of the transmitter to operate a different key from that depressed on the preceding operation in order to release the latter and initiate the new cycle. This would necessarily bring about a turning of the cylinder 82 through at least one step. Even in the Fig. i system, however, this need not result in the pulsing of the escapement but might result merely in a turnback operation of the printing ai -heel for the new printing operation when the preceding printing operation did not involve such a turnback.

Another distinction between the systems of Figs. 1 and 3 is that in the Fig. 1 system the duration of the printing period is predetermined by the time interval allowed by the operator in depressing successive controlling keys [9. The operator is required to delay sufficiently between the depression of successive keys to afford time for the necessary partial rotation of the control cylinder [2 and the subsequent operation of the printing devices. In the Fig. 3 system, on the other hand, a special timing means similar to that disclosed in the Ackell and Paulding patent above mentioned, is provided. This timing means, which comprises a driven shaft, is released for its timing cycle and for the performance of certain operations incident to the transmission or the desired printing signal upon the stopping of the main commutator brush arm which controls, the transmission of the pulsing signals sent out to the various printers in the manner to be hereinafter described.

In the Fig. 3 system, it should also be observed that the arrangement of the characters on the printing wheel of the various printers is difl fili ent from that heretofore considered desirable for printing telegraph purposes. The new arrangement is such that the characters which aremost frequently encountered in the transmission of the desired messages are in those positions on the printing wheel which do not require the turning back of the printing wheel to effect printing therefrom. Those characters which are encountered less frequently in the transmission of messages are placed in the intermediate positions which require a turnback of the printing wheel to effect printing therefrom. The particular relative positions of the characters in each of the two categories above m ntioned is'd et'ermined in accordance with the principle heretofore em ployed in the location or" the characters'about a printing telegraph wheel, i. e., in accordance with the frequency Of occurrence of various combinations of characters. In conformity with the foregoing principles, the characters in the new construction are arranged about the printing wheels in the following sequence: those characters 10 eated in the positions not requiring a turnback of the printing" wheel to effect printing therefrom are in the order of Space, B, T, P, C, P1,,L, M,

E, A, U, I, O, N, G, R, F, D, Y, and S, while those characters requiring a turnback of the printing wheel to effect printing therefrom are arranged in the order Cr, Q, J, W, V, K, it, 3, 5, 7, 9, X, &, Z, 2, 4, 6, 8, and period. These latter characters are interspersed between those of the first series and in each instance they precede those of the first series. Thus Or is in advance of space, Q is in advance of 13, etc.

In considering the schematic showing of Figure 3 it should be understood that the transmitter resembles, in a general way, that illustrated in the above mentioned Ackell and Paulding patent. The new construction diifers, however, in detail from that of the patent chiefly because the controlling tape is of the 5 hole, rather than the 8 hole, type. This necessitates specific differences in the form and arrangement of the commutator, collector rings, and cooperating brushes. There are but two annularl disposed series of commutator segments, each having its own collector ring, one preferably continuous and the other subdivided. The brushes cooperating with the commutator segments and the collector rings are carried by two arms which in themselves are conductors but which are mounted in an insulating block secured to the rotating shaft of the transmitter.

Referring now to Figs. 3a. and 3b, the rectangular block designated till at the top of the figures represents diagrammatically the collector ring associated with the pulsing commutator which is in turn represented diagrammatically by the series of equally spaced and equally long'blocks designated H12. In the actual construction of the transmitter the collector ring itll is preferably provided as the innermost ring, while the commutator segments H32 are preferably provided as the adjacent ring of the commutator assembly. The next ring of the commutator assembly is a divided collector ring having a number of small segments of equal size and several larger segments of diiferent lengths. These, collectively, are diagrammatically illustrated by the blocks 33. The sections, or segments, are interconnected in accordance with 3 groupings as will be explained'more fully hereinafter. One of these groups of segments is identified with letters, another group is identified with figures, and a third group is identified with both letters and figures.

The reason for this third group is that certain characters are made to perform a double duty. i. e., one represents either the figure 1 or the letter 1, and similarly represents the figure 0 or the letter 0. So, also, the carriage return and space positions of the divided collector ring of the commutator are classified as either figures or letters, so that they will be effective regardless of whether the figure shift or the letter shift is effective in accordance with the common practice in the hole tape system.

The outer series of commutator segments in the preferred construction is identified with the various characters and special signals to be transmitted, and thus broadly corresponds with the key stops of the Figure 1 arrangement. These segments, which are diagrammatically represented b the blocks we, are of equal size and, it will be noted, there are two such commutator segments for each of the segments Hi2. At the left end of the development of the commutator and collector ring members shown in Figures 3a and 3b there is graphically illustrated the pair of brush carrying arms m5 and use, each arm carrying two brushes adapted to be shifted over the 1-2 commutator segments and collector ring sections with which they are associated and which they are intended to interconnect in the operation of the device in the manner to be described. The sectors or segments which are in vertical alignment will be simultaneously engaged. The two arms, it will be noted, are insulated with respect to each other as indicated at I01. In the actual construction, it will be understood, the arms are rotatably mounted about the axis of the commutator assembly, but for purposes of illustration they are indicated as though movably mounted longitudinally along the development of the commutator assembly. Itshould also be understood that the shaft carrying the brush arms H35 and 208 is arranged to be driven through a friction drive from any suitable source, such as a motor. Whenever desired the brush arms may be stopped while the friction driving means, which serves to rotate the shaft ma continue. In the schematic showing a ratchet segment N18 is indicated, which should be understood to represent a complete ratchet in the actual mechanism. With this a pawl I09, which is spring urged into engagement with the teeth of the ratchet, cooperates to arrest the brush arms and their supporting shaft at desired intervals during the operation of the machine. As will be explained more fully hereinafter, the operation is such that the brush arms will be permitted to sweep over the commutator and collector sections until the commutator segment I66, which has been predetermined by a particular series of holes in the tape that controls the transmitter, has been reached by the corresponding brush.

In fact the arrangement is such that the tooth of the pawl its cooperating with a tooth of the ratchet 108 will stop the indicated brush just as it reaches substantially the far or righthand end of the commutator segment. This allows the necessary time for the completion of the circuit which brings about the release of the pawl I09 and also time for the operation of the pawl by its spring H180. to effect the desired stoppage of the brush arms.

The arrangement by which the brush arms are brought to rest upon the desired commutator segments involves a plurality of relays l I 0, arranged in what may be described as a fan bank, and which are under control of the pins of the tape analyzer designated generally by the number I I l. This is generally similar to the tape analyzer disclosed in the above mentioned Ackell and Paulding patent. There are, however, only 5 pins, H2, H3, H6, H5, and H6 in lieu of the 8 pins of the prior construction and the arrangement is such that any number of these pins from O to 5 may pass through the tape in a single operation. When the pin H2 passes through an opening in the tape, it serves to shift all of a group of relay arms Ill associated with the pin H2 toward the right, as they are shown in the diagram. A suitable frame or bar, not shown, may be provided to interconnect these arms for operation in unison. If at a particular position on the tape there is no hole for the pin l 12, the arms I ll identified with the top row of the fan bank will be held to the left in engagement with the opposite contacts. Similarly the pin 483 when permitted to pass through an openin in the tape will cause all of a series of interconnected relay arms H8 to swing toward the right, whereas when no hole is in registry with this pin, these arms will be held in engagement with the opposite or lefthand contacts. In the same manner relay arms H9 are associated with the an M4, that aims 12 are associated wit the 1am iI5, and=a relayarmI21 is associated v i-1th the pin H 8. {In the construe;- tion illustrated there are rela arms 5W, 8 relay arms Ht, lrelay a rm's M9, 2 relay arms I 25, and a single relay arm i2 1. These provide for the 32 cornmutationsiand permutations permitted by theseriesdf 5 ho1es in the tape.

As will appef mor man hereinafter, the arrangement is ting bf the analyzer piiis blilfVdh Circil'it will be completed from the relay arm *IBi to one of the 32 contacts engaged by the relay arms i il. Ail of the other 31 circuits il be'broken at onepoint or another. Each of the-32 Contact points associated with the relay i i is connected with at least oneo'f the commutator segments life, with the exception of the contact the eiitreme lefthand end of thes'eries, whose purpose will be described hereinafter "any of the 32 contacts will be'con'n'ected with" oseparate segments IE4, while in some instances two separate contacts, of the 32 engaged by the relay arms ill, will be connected 'wi sinjle commutator segment 1M.

There are '40 -such commutater segments in the illustrative arrangem-eht and these are connected with 3 10f the --coi1tacts engaged by the arms ill. As will appear-mere-clearl-y hereinafter, the selection of the desired the -"of the two commutator segmentsid i, predetermined by the .set'tingroi the pins H2, H3, ri l, Hiijazid 'i it, is-eiiected the settingof a series of rei'ays responsive to the conventional letter and "figure shift signals predetermined by the tape. The arrangement in this regard is such that prior to the transmission of 1 a particular character 'signala shift signal may be set up bythe tape anai zerand this 'Wi'ii affect only the transmitter. itserves simplyto shift a series of interconnected relay arms E23 either toward the right as shown or toward the left. These arms are associated witha polarized relay and will, therefore, remain in any position in which they are set until rese't by another shift signal. In the layout illustrated, therightha-nd position of the arms r23 corresponds with the letter shift signal of the which is constituted by a series of 5 holes. The lef-thand position of the relay arms 523 corresponds with the figure shift signal of the tape and isrepresented by holes aligned with the pinsHK-Ht, H5, and 9%. Thus in 'a'typica1-imtame; ssuming that the tape at aparticular positien is provided with holes in line withthe M2, M5, and it, a circuit will be completed through the relay fan hank "iii; to the contact F24 identified riththe characters W and 2. This'contact isconnecte'd with both of the segments and I26 ofthe commutator sec tion IM. The determination as to whichoi these segments I I23 is to be effective in stepping the brush arm's Hi5 and m5 is made bythe adjustment of relay arms E23. If-these are set inthe position illustrated-in Figure 3, because of the prior transmission of a letter shift signal, the segment @235 will beeiiective, whereas if the relay arms had-been shifted to the left, by the prior transmission-of a figure shift signaLthe segment 526 would have been effective.

When the brush arms Hi5 and 4% are brought to rest'bythe completien of'a circuit through: the

selected oneof the commutator segments its, a

print timingshaft i2? will be released for rota tion through a half turn. This is-accomplished by the dis'enga'ge-"ment of apawlitfi from a tooth T29 on adisufl'fi sc d to the-piifit tin'iing Shaft which is, in turn, dri'ven tliro'ugh a frictional h that-roran -parueu1ar set carnation with the driving rector of the mitter, a manner wen lrnow'ni-n tlieejrt. 'T'i v'o cams 3'35 and P32 harried by the printer timing shaft 121 serve to operate switch arms its and i3 i respectively-at appropriate points in the cycle to perform the functions to be hereinafter tescribed.

the movement of the brush arms W5 and T6 over the commutator segments, in the manner above explained, the "brushes carried by the arm I lifi w'ill completecer'tain pulse transmitting circuits between the commutator egments T02 and the'collectorring I0 I. Alternate ones of the commutator segments are connected with a line I35 which is,inturn, connected with the positive sid'eof "a current source I35, whereas the remain'- ing commutator segments "of the group 162 are connected through a line I37 with the negative side of a current source I33. It should be understood that these commutator segments, sepa rated by the intervening insulating spaces on which the brush whichsweeps over the segments I02 ma "come to rest, will function in the transmission of the pulsing segments to the distant printers in substantially the same manner as the commutator M of the Fig. 1 system. Certain'differences between thefunctionings of the two systems, however, will be mentioned hereinafter. One difie're'nce which may be 'notedat this time is that the signals transmitted to the distant printers are not derived directly from the current sources I36 and I33, but are derived instead from'current sources I39 and lit, which respond to the pulses of the current f'romthe sources I36 and I38. While two generators in -series"are'indicated as the source of the current'which'alternate flows in opposite directions, it will be understood that other means for "accomplishing the same purpose may be substituted. A positive pulse emanating from the source I 38 is passed through a rectifier IM, thence "through a relay coil 2, back through another portion of the rectifier I4 I and thence through a line I43 to and through a polarized relay "I44 to the collector ring Ifll, thence through the brushes and brush arm I05 to one of the commutator segments I02 connected with the line 131. In energizing "the relay I44 in this manner, its armature [45 will have been swung to the left to send out a new pulse over the series'of transmission lines I46 to the distant printers. This signal will have come from the positive side of generator I39, through a line I 41 to the transmission lines M6, thence back through the line M8, armatii'res I49 and I45 to the negative side of the power source I39.

An advantageof this arrangement of dual power sources I36, I38 and I39, is that onlypositive and negative pulses will be sent out over the lines I46 even though open pulses of brief duration may be produced in the circuits supplied by the power sources I3t and I 38 as the brusnsw'eeps over the gaps between the commutator see ments I02.

Let us now trace certain specific circuits which are completed inthe course of a series of operations of the apparatus such as those,"for example; involved in transmitting the series of signals graphically illustrated in Fig.5. We will assume that appropriate switches have been thrown to connect the apparatus schematically shown in Figs. 3a and 3bwith one or more suitable sources of direct current which are graphically indicated. Let it also be assumedthatthe various outlying 3a; and 3bliavepreviouslybeenset in operation,

this having been accomplished, as will be described hereinafter, by simply placing in operation, in any suitable way, the current sources I39 and I40. Let it also be assumed that prior to the transmission of the series of signals represented by Fig. 5, the last signal was that effecting printing of the letter P. In the course of the printing of the letter P a magnet I50 will have been energized, in a manner to be hereinafter more fully explained, to retract the pins of the :analyzer III and the tape passing through the analyzer will have been shifted forwardly one step to position the next series of openings in the path of the pins. Also during this printing operation the magnet I50 will be de-energized and the pins will be permitted to rise wherever possible through the openings in the newly positioned portion of the tape. Under the assumed conditions a series of openings will be provided in line with the pins H2, II5, and H6 thereby predetermining the character W. This is, of course, on the assumption that the last shift signal transmitted was a letter shift. The movement of the specified pins through the openings in the tape will bring about the shifting toward their righthand positions of all of the relay arms in the groups II1, I20, and I2I, whereas the relay arms of groups H8 and H9 will remain in their lefthand positions. Tracing the current from the negative side IEI of the current source, it will be found to pass firstly through the coil I52 of a polarized relay which determines whether the system is to effect a character selecting operation or a printing operation. From this coil the current passes toand through the arm I2I of the first relay, thence through the line I53 to and through the righthand relay arm I20a, thence through the line I59 to and through the relay arm II9a, to and through the line I55, through the relay arm II8b to the line I56, and thence through relay arm Iild to the contact I24. .The latter, as has previously been explained, isconnected by suitable wiring to both of the commutator segments I25 and I26. When a circuit can be completed through the segment I25 by the bringing of the associated brush on the arm I96 across this segment, the balance of the circuit will be completed through the collecting ring section I51 and line I58 to and through the righthand armature I23a, and thence through the line I59 to the positive side I of the source of power. 7

Movement of the brush arms I and I06, to permit the completion of the circuit through the commutator segment I25 in the manner. explained, is permitted by the withdrawal of the pawl I09 from the ratchet I 08. This isaccom plished in the following manner: Current from the positive side I 6I of a current sourceflows through a coil I62 of a magnet capable of re tracting the pawl I09, thence through a line I63 and through an armature I64 to the negative side I65 of the current source. Armature I64 will have been moved into engagement with the contact at the end of the line I63 by a current passing through a relay coil I66. Current for 7 I33 it will be noted, is held against the contact at the lower end of line I10 by cam projection I'IZ on the cam I3I secured to the print timing shaft 21. Release of the ratchet I08 in the manner indicated, will, under the assumed conditions, allow but a single step of movement of the arm I96 to carry its brush from the previously engaged segment P to the segment W, designated I 25, which, as previously indicated, will complete the circuit through the relay fan bank. Completion of the circuit through the fan bank in this manner energizes the coil I52 of the polarized relay thereby pulling the armature I 69 toward the left into the position indicated in Fig. 3. This breaks the circuit previously traced through the armature I69 and the relay coil I66 and releases the armature I64 to break the circuit through the magnet I62 and thus releases the pawl I09 for re-engagement with the ratchet I08. The mechanism just described will respond with suiiicient rapidity to insure stoppage of the brush on the W segment designated I25.

Shifting of the armature I69 to the left in the manner indicated'completes a circuit from the negative side Ill of the current source through the line I26, through the armature I66, through a line I13, a branch line I14, to and through a relay armature I15, and thence through a line I16 and a branch line I11 to and through a coil I18 of another relay, thence through a further relay coil I19 and a line I80 to and through an armature I8i to the positive side I82 of the current source. In passing through, the relay coil I10 the current will pull-up on the armature I83, thereby completing a circuit from the positive side I89 of a current source through the armature I82, a line I85, and a magnet coil I86 to the negative side I81 of the current source. Magnet coil I will attract the pawl I28 and thereby disengage it from the projection I29 on the stop disc I30 secured to the print timing shaft I21. A half rotation of this shaft will thus be permitted. Passage of the current through the coil I19, as explained above, will have served to throw to the left, as shown, an armature I88 of a polarized relay to complete a circuit from the negative side I89 of a current source to and through a line I90, then to and through coil I50 to the positive side I9I of the current source. Coil I50, as has previously been explained, serves the purpose of retracting the feeler pins of the analyzer and it serves also to operate a ratchet which advances the tape to the next position, in any convenient manner, not shown.

Upon the commencement Of the rotation of the shaft I 21 the projection I12 will be rather quickly carried away from the end of the arm I33 and will permit the latter to be drawn by the spring connected therewith toward the right. This serves to break the circuit which was previously completed through the arm I33, line I10, armature I69, line I13 down to and through the coil I18, etc. in the manner previously explained. Breaking of the circuit to the coil I18 serves also to break the circuit through the coil I86 and thus releases the pawl I28 to arrest the printing shaft as the stop I29a is brought against the tooth of the pawl. Simultaneously with the breaking of the circuit explained above, a new circuit is completed from the negative side I1I of the power source through the arm I33, thence through a line I92, through a coil I93 of the polarized relay acting upon the armature I88, thence through a coil I94 of the polarized relay acting upon the armature I69, thence through a coil I95 of a 17 further relay, through a line I96 and the arm I34 to the positive side I9! of the current source. In passing through the coils I93 and I34 it will be understood that the armatures I88 and IE9 will be shifted toward the right and will so remain until the coils Il9 and I52, respectively, are energized again.

As has previously been indicated, the shaft I21 serves the purpose of timing the printing operation of the system. So long as the shaft I2! is held stationary with the projection I12 operating, upon the arm I33, the system may be said to be in the selecting condition and during this time only positive and negative pulses will be transmitted over the lines I 5. On the other hand, when the shaft I2'I begins to rotate to carry the projection I12 away from the end of the arm I33 an open signal of some duration, the length of which may vary according to the particular position at which the brushes are stopped at the end of the preceding selecting operation, is sent out over the lines I66. During this period, it is impossible to send a selecting signal over the lines because the circuit from I 31 to I'll will be broken at the arm I33 and the pawl I09 can, therefore, not be retracted.

We shall now describe the production of the signals transmitted over the lines I46 incident to the movement of the brushes from the P segment to the W segment of the commutator I64 and incident to the succeeding printing operation. As the brush associated with the commutator ring IE4 shifts from the P segment to the W segment, the brush associated with the commutator m2 shifts from the segment I38 to the insulating space Ids and remains there. In the course of this shift the circuit through the generator I33 will be broken, thereby ole-energizing the coil I42 and releasing an armature 203. It should be mentioned here that coil I42 would not have been de-energized to release the armature 200 if the brush had simply passed over the insulation I39 and had not come to rest on it. Armature 233, prior to its release, completed a circuit from the positive side 2!)! of a power source through a relay coil 262, armature 256, line 203, armature 254, line 285, and an armature 263 to the nega-- tive side 2M of the power source. In passing through the coil 2&2 of the circuit just described, the power served to hold the armature his toward the left and thus kept the circuits through the lines I45 closed. Upon the release of the armature 23%, however, in the manner explained, the circuit through the coil 282 will be broken and the armature I49 will be released to open the circuits through the lines I46.

In accordance with the system, as previously explained, the opening of the circuit at this time should be of the long printing duration and this is brought about as follows: It is determined by the time required for the shaft 'I2'I to rotate sufiiciently to carry a bump 208 on the cam disc I32 against the lower end of the arm I34 so as to shift the latter toward the left. This serves to close a circuit from the positive side I91 of the power source through a line 209 and a coil ZIIi of a polarized relay to the negative side 2!! of a power source. The current in passing through the coil 2H} serves to shift an armature 2!? of the polarized relay toward the left, as shown in Fig. 3b and thus closes a circuit from the negative side 20? of the power source. through a line 2I3 and the armature 2I2, thence through a line 2I4, through the coil 232 to the positive side 2M of the power source.

will be seen, swings the armature I49 to the left again and terminates the open signal which has been transmitted over the lines I46.

Referring now to the diagram of Fig. 5, the section 2I5 of the current flow line represents the open circuit condition just described, during which the letter W will have been printed. As indicated by this diagram the shifting of the armature I49 toward the left in the manner explained at the completion of the printing cycle serves to restore the previously existing circuit which, in the example indicated, involved the transmission of a positive signal associated with the letter P. This is illustrated by the section 2H5 of the current flow line in Fig. 5. It will be appreciated that since this signal is of the same character as the last pulsing signal transmitted over the lines I55, it will not effect any movement of the escapement mechanisms of the various printers. This conditions the sending circuits I45 for the transmission of whatever signal it may be desired to transmit next. It may, if desired, be simply another open signal in the event that it should be desired to print the letter W again.

The arrangement is such that a maximum amount of time is permitted for the readjustment of the pins of the analyzer I II and the relay fan bank armatures after they complete their function of determining the position in which the brush arms I and I06 are arrested. It should be noted in this connection that upon the swinging of the armature I59 toward the left, as the coil I52 is energized, while the bump M2 on cam disc I 3| holds the arm I33 toward the left, a circuit will be completed through the coil I50 to retract the analyzer pins and shift the tape to the next position. This, as previously explained, is accomplished by the swinging of the armature I38 toward the left b the current passing through the coil I'I9. Release of the pins is accomplished in a relatively brief period after the commencement of the printing cycle by de-energizing the magnet Ito through the shifting of the arm I33 toward the right as the bump I72 is carried beyond the end of the arm I33. This movement of the arm I33 breaks the circuit from the source In through the armature its, coil l'I9,etc. and thus allows the armature I85 to be swung toward the right upon the energization of the coil I 93. This, as explained, results from the swinging of the arm I33 toward the right to complete the circuit from the negative side ill to the positive side I91 of the current source.

It should be noted further that toward the end of the half revolution of the shaft I'Z'l, the projection 2833 on the disc I32 acting upon the arm I34 will break the circuit from the source I3'l to the negative side I'll, thus deenergizing the relay coils I93, I34, and I95. The arms I59 and I88 will, however, remain toward the right until they are again shifted toward the left by the energization of the coils I52 and I19, respectively. It will be understood that at the completion of the printing cycle the parts associated directly with the shaft I27 will assume the position indicated in Figs. 3a and 3b.

Returning now to the assumed series of signals represented by Fig. 5, the new position of the tape aligned with the feeler pins IIZ to H6, inclusive, will have perforations representing the letter 0, these being opposite the pins H2! and H3. It is assumed, of course, that the transmitter is still operating on the letter shift side This, it 15 since no figure shift signal has been transmitted the power source I3t.

19 subsequent to the printing of the W. Tracing the circuit that will now be completed through the relay fan bani: IIt from the negative side I5I of the current source to the positive side I50, this will pass through the relay coil I52, armature I2I, line 2I'I, relay arm I201), line 2I8, relay arm lied, then relay arm II8h, then through relay arm I I'Io to the terminal 2 I3 identified with the characters and 9. This terminal is connected through the line 220 with the segment 22I of the commutator section I04 identified with the number 9. A branch line 222 extends from an intermediate point of the line 229 to the middle armature I232) of the series of three shift relays and from the latter to a segment 223 of the commutator Iii-2 identified with the letter 0. It will be noted that upon the completion of the previous printing cycle of the shaft I2? the circuit from the negative side III of the source of power will have been completed through the relay I66 to the positive side I67 of the current source and this, in turn, will have closed the circuit through the magnet I62 and will have released the brush arms for movement from the W position or the commutator 554i to the new position determined by the new setting of the feeler pins. Of the two sections 22H and 223 of the commutator I54 to which the circuit from the source I5I may be traced through the fan bank, only the section 223 is capable of completing the circuit to the positive side of the current source through the brush arm its. This is because a segment 22d of the collector ring I63 is connected with a line 225 which connects with a line 226 extending toward the left to a contact 22? where the circuit is broken by the position of the armature I23a. Following the line 22% toward the right, it will be found to extend downwardly to and through a coil 223, thence upwardly through a coil 229 and then through a line 230 over to a contact 23I where a break in the circuit will again be encountered. The segment 223, on the other hand, is capable of completing a circuit through its related section 2 32 of the collector ring I03 by virtue of the connection of the latter through the line 233 with the positive side I59 of the current source. In shifting from the segment I25 of the commutator IsIJG to segment 223, in order to complete the circuit through the fan bank, the brush arm I85 will carry the brush associated with commutator I02 across a number of the segments of commutator I92 and across a number of insulating spaces between these segments, thereby sending out a succession of positive and negative pulses over the lines M6 in the manner hereinbefore explained. Thus in shifting from the insulating space I99 to the segment 23 a circuit will be completed from the positive side of the power source I36 through the line I35 to the segment 233, then through the brushes and brush arm to the collector ring ItI, through the relay coil Me and line I43 back through the rectifier MI and relay I52 to the negative side of Passage of the current through the relay I22 at this time will serve to draw the armature 2% toward the left and thus close the circuit from the source 2ilI previously traced through armature 253, line 203, armatures 2% and 236 to the negative side 26? of the source of power, thus paralleling the circuit which has already been completed between points 2M and 25? through the line 2M. In this connection it should be noted that the direction of fiow through the coil Mil is opposite to that last flowing through this coil and, therefore, the armature I45 will be swung toward the left. This will break the cir cuit from the power source I40 and complete a circuit from the power source I39 through the transmitting lines ME. A pulse of opposite sense to that last transmitted is sent over the lines, as illustrated by the section 235 of the current flow line on Fig. 5.

Now as the brush on arm I05 moves across the next insulating section 236 of commutator I02, there will be a temporary interruption in the flow of the current from either of the sources I36 and I38. This interruption, however, which stops the flow of current through the relay coil I42 is not of sufficient duration to permit the spring associated with armature 200 to draw the latter toward the right. This particular relay, it will be understood, responds slowly enough to permit this slight interruption without opening the circuit through the armature 290. As the brush on the arm I05 now moves to and across the segment 23'2 of the commutator I92, current will flow from the positive side of the current source I38 through the rectifier I4I, coil I42, line I43, polarized relay MG, collector ring IIII, segment 231, and line I31 back to the negative side of the current source I38. The direction of flow of this current through the coil I44 is opposite to that last flowing through this coil and will, therefore, shift the armature I45 toward the right again. This will cause a pulse of opposite sense to be sent out from the current source I iIl over the lines Hit. The same conditions as explained above will be repeated several times as the brush on arm I65 is carried across the successive sections of commutator I62, and the insulating spaces between these sections, until the brush is finally brought to rest upon the section 233 of commutator I02. The series of pulses sent out over the lines we in this manner are graphically indicated in Fig. 5 up to the final pulse 239 which precedes the short open signal 240 indicated in this figure. We shall now explain how this short open signal is produced.

The brush on arm I55 having now reached the segment 223, identified with O in the manner explained, the circuit previously described through the fan bank Ilil will have been completed. From the negative side I5I of the current source through the relay coil I52, and the other connections previously explained, to the positive side I58 of the current source. In flowing through the coil I52 this current will serve to draw the armature H59 again toward the left, thus breaking the current from source III to the positive side I6 1, thereby breaking the current through the coil I52 and releasing the pawl I09 for engagement with the ratchet I88 to stop the brush arms with one brush on segment 223 of commutator I94 and another brush on collector section 232.

Swinging of the arm I59 to the left serves to complete a circuit from the negative side I'll of a source of current, through line III), armature I65, a part of line I13, a branch Zfil, armature 2 32 which will be at this time held toward the left by its spring, thence through line 243 and a relay coil 244 to the positive side 2245 of the source of current. Passage of the current through the coil 2% in this manner serves to swing the arm 2I2 of the polarized relay toward the right thus breaking one of the two parallel circuits extending from the negative side 25'! of the source of current up to the positive side ZIlI through coil 202. This is for the purpose of pre paring the system for a subsequent opening of the other of the parallel circuits so that coil 292 may be de-energized in the manner to be explained. Also the swinging of the arm I33 toward the left serves to complete the circuit from the negative side III of the source of current through line Ilil, armature I69, lines I73 and I14, armature I15, lines I76 and Ill, coils I'I3 and H9, and line I83 to the positive side I82 of the current source. This current in flowing through coil IlS attracts armature I83 thereby completing a circuit through the coil I83 and withdrawing the detent I28 from the disc I39 on the print timing shaft [21. At the same time, the current flowing through coil I19 tends to shift the armature I83 to the lefthand position shown in Fig. 3. Swinging of the armature I88 toward the left, in this manner, will complete the circuit previously described from the negative side I39 of the power source through line I99 to the magnet I59 for withdrawing the feeler pins of the analyzer and shifting the tape to the next position. Rotation of the shaft I21 will promptly bring about the release of the arm I33 thereby breaking the circuit from the source I'II through the armature I69, etc., thereby releasing the armature I83 and breaking the circuit through coil I36 to permit the pawl I28 to return to its stopping position in engagement with the next tooth I29.

Simultaneously with the breaking of the circuit, as last mentioned, the shifting of the arm I33 upon the movement of the bump I72 beyond the lower end of this arm serves to close the circuit from the negative side III of the power source through the line I92, through coils I93, I94, and I95 to the positive side IQ! of the power source. This current in passing through the coil I93 shifts the arm I88 to the right again thereby breaking the circuit through the magnet I59 and permitting the feeler pins to assume their new positions. Flow of the current through the coil I94 shifts the armature I69 to the right again,

thus preparing the circuit through the coil I33 for a subsequent operation at the completion of the printing cycle. Flow of the current through the coil I95 serves to attract an armature 245 thus completing a circuit from the negative side 24'! of a source of current through a condenser 248, thence through the armature 243 and through a line 249 to a coil 250 connected with the positive side 25I of the current source. This flow of current through the coil 253 will attract the armature 203 and thus break the circuit through the second of the two parallel circuits from the negative side 231 of the source of current up to and through the coil 232 to the positive side 2III of the source of current. Accordingly, the armature I49 will be released and an open signal will be sent out over the lines I43. The length of this open signal is determined by the condenser 24-8 since this will permit an adequate flow of current from the negative side 247 to the positive side 25I only so long as is required to charge the condenser to a predetermined extent, as explained in connection with the condenser 59 in Fig. 1. This time interval is represented by the section 240 of the current line indicated in Fig. 5. When the condenser 243 is charged to a predetermined extent and the current flow through the coil 259 is reduced, armature 233 is released to complete the circuit from the negative side 231 of the current source through armature 296, line 265, armature 294, line 293, armature 290, and coil 292 to the positive side 2! of the current source, thus attracting the armature I49 and transmitting over the lines I46 a pulse of the same character as existed prior to the short open. This is indicated by the section 252 of the current line on Fig. This condition continues until the next bump 233 on the cam E33 engages the arm I34 to shift it toward the left, thus breaking the circuit through the coil I and releasing the armature 243 to permit discharge of the condenser 248 through a resistance 253. Shifting of the arm I34 again establishes the circuit previously explained from the positive side I91 of a current source through line 233 and coil 2 I 3 so that the latter shifts the armature 2ll2 toward the left again, thereby completing the other of the two parallel circuits between sides 29'I and Zill of the current source. The conclusion of the printing operation in which the bump 293 passes beyond the arm I34, while the bump II2 of cam I3I engages the arm I33, is the same as previously described in connection with the printing of the letter W. As previously indicated, shifting of the arm I33 in this manner serves to complete a circuit through the coil I35 which, in turn, completes a circuit through the coil I32 to retract the pawl I39 and thus permits the movement of the brush carrying arms to the next position.

Assuming now that the new group of holes in the tape at the ieeler pin position are identified with the carriage return signal, an opening will be provided in line merely with the pin H3. This will result in leaving all of the relay arma tures of the I25, I33, H3, and Ii'. groups toward the left (Figs. 3a. and 3b), whereas the group of relay armatures I I3, including that designated 3h, will be shifted toward the right. Accordingly, as the brush arms I35 and I33 carry the brushes over the commutator segments, a circuit will be completed from the negative side of the source IEiI through coil I52, armature I2I, line 2H, armature Ifziib, line 2I3, armature II9d, then armature H812, and armature II'Io to contact 254 which is connected through a line 255 with a coil 253 and then through a line 25? with the commutator segment 353 designated Cr in the commutator I34. The circuit is completed when the cooperating brush strikes this segment by the electrical connection through the brushes to the collector ring section 259 and thence through the line 233 to the positive side I33 of the source of current. It will be understood that as the brush arms shift to the new position from the 0 position in which they were last held, a series of alternate positive and negative pulses will be sent out over the lines I43 by the engagement of the brush on arm I35 with the successive segments of the commutator I32 from the position 2133 to the end of the diagram in Fig. 3b and then to the segment 23% at the lefthand end of the showing of the commutator in Fig. 3a. Actually, of course, the commutator segments are arranged in a circle so that the transition from one end of the line to the other is the same as in shifting from one to the other of successive segments illustrated in the diagram. The brush arms are arrested when they reach the insulating section 23I of the commutator and hence an open sig nal is sent out over the lines I43. This, it will be understood, is due to the breaking of the circuit through rectifier I4! and coil I42, thereby releasing the armature 239 which, in turn, breaks the circuit through the coil 232 and releases the armature I43. It will be recalled in this connection that upon the completion of the circuit through the fan bank, as the brush 23 reaches the carriage return segment 258, a circuit will be completed from the negative side Iii of the current source through the armature through the branch line Z li, armature 222, line 2 2 3, and coil 2% to the positive side 245 of the current source. This serves to shift the armature 252 toward the right and thus opens one of the two parallel circuits through the coil 282. Such opening of one of the circuits occurs before the brush on arm IE5 reaches the insulating space 265 so that as soon as the latter is reached and the armature 288 is shifted toward the right in the manner explained, both of the circuits through the coil 2&2 will be opened to transmit the open signal over the lines MS. The duration of this open signal will be considerably greater than an ordinary printing signal, even of the long type hereinabove described. This is due to the fact that the passage of the current through the coil 25:3, in the manner explained, serves to draw the armature I toward the left thus breaking the circuit which would normally be made through this armature to the coils H8, I79, etc. In lieu of passing through these coils, the current from the negative side of the current source I'll passes through armature Hi9 and line P53, then branch ii i, armature H5, branch 262, relay coil 263, and thence through choke coil 264 to the posi tive side 265 of the source of current. The action of the choke coil 2% is such as to require a predetermined length of time to build up sufficient current to enable the relay coil 2 53 to shift its armature 2% toward the left. When this finally occurs the current, which in the ordinary printing operations passes through the armature H5 and line lit, in the manner previously explained, will now pass through the branch to and through the armature 266 and thence through the line ill and the balance of the circuit to the positive side I82 of the Source of current. The pawl E28 will then be retracted, in the manner previously explained, to set the print timing shaft it? into operation. Thus the duration of the open signal transmitted over the lines hi6 will be determined by the length of time required to build up the necessary current through the choke coil 25% and then by the action of the timing shaft I2? in the same manner as for a printing operation of the longopen type. This extra long-open signal, indicated graphically by the portion 2538 of the current flow line in Fig. 5, will operate through any suitable mechanism such as that disclosed in the patent to Landfear, No. 765,978, granted July 26, 1904, to release the carriages of the printers and permit them to be returned by their springs toward the hilt. Line spacing of the paper also takes place at this time. During this prolonged printing cycle the printing platen will be operated as in a normal printing operation but the type wheels of the printers, being in their carriage return positions, will have a blank space opposite the platen so that no printing will take place. It will be understood that, as in a normal printing operation, the relay armature I59 will be shifted toward the right in the course of rotation of the shaft i2? and will thus break the current to the relay coil 2% and the choke coil 26 so that the affected circuits will be restored to their normal conditions. Therefore,

upon the completion of the half revolution of It will also be understood that in the course of the half revolution of the shaft I21 the analyzer pins will have been retracted, the tape fed to its new position, and the analyzer pins released for their new setting. Assuming now that the new position on the tape is that representing a figure shift, holes will be provided in the tape in line with the pins IIZ, H3, H5, and MB. This will prevent the completion of a circuit through the armature I69, such as normally occurs to and through the line I68, coil itii, etc. and which normally retracts the pawl I99 associated with the brush arms I65 and I06. The reason for this is that, immediately upon the shifting of the relay arinatures of the fan bank in response to the shifting of the indicated feeler pins, identified with the figure shift designation, a circuit will be completed from the negative side I5I of the current source through the armature I2I, line I53, armature I2Eia, line H54, armature II9a, line I55, armature IIiib, line 269, and armature IIlc to the contact 2% identified with the figure shift. This contact is connected through a line 27! with a coil 272 and then through a line 213 with a coil 214 and on to the positive side 215 of the power source. This circuit will be completed before the shaft 52? completes its timing cycle for the preceding carriage return operation and, therefore, the armature I69 will have been shifted to the lefthand position by the coil I52 before the circuit which brings about the release of pawl I99 can have been completed.

It should be observed that upon the completion of the printing cycle for the carriage return, as represented by the section 258 of the current flow line in Fig. 5, the same type of signal will be sent out over the lines MS as was last sent out. This, in the assumed series of signals, would be a negative pulse determined by the segment 2% of the commutator H12. It is indicated in Fig. 5 by the part 2'i6 of the current flow line.

Now on completing the circuit through the coil 214, in the manner explained, the armature 252 will be drawn toward the right to complete a circuit from the positive side 215 of the current source through coil 214, thence through a branch line 2'37, through armature 242, line 2, and through the armature I69, line Ill], and arm E33 to the negative side I'lI of the source of current. This serves to hold the armature 242 shifted toward the right, even though the circuit through the fan bank may be opened. It should be noted in this connection that normally, upon the completion of the half cycle of the shaft i2'i, the circuit through the fan bank will be broken by the engagement of the bump I 72 with the arm I33 serving in the manner previously explained to complete a circuit from the negative side I of the source of current through the retracting coil I50 for the feeler pins. The breaking of the circuit through the coil 214, which was predetermined by the previously shifted feeler pins identified with the figure shift designation, will not result in de-energizing this coil because the new circuit through the armature 242 will have been made. The purpose of this holding circuit is to prevent the transmission of an open signal over the lines I55 in response to the figure shift designation on the tape. Thus the current which would normally flow from the negative side I'll of the current source, through line Iii armature IE9, line 24!, armature 242, and line 253 to coil 2% and positive side 245 of the current source will, under the assumed conditions, be broken at the armature 242 by the maintenance of this toward the right. This, therefore, prevents the coil 244 from shifting the armature 2l2 toward the right to break the circuit from the negative side Zfil of the current source to the positive side 2M and thus prevents de-energization of the coil 202 so that no open signal will be transmitted over the lines.

As a result of this, the negative signal commenced at 2% (Fig. 5) in the manner above explained, will continue until the system is prepared to send out a positive signal over the lines I45 as will be explained presently. However, before passing on to the next cycle of operation of the system, it should be pointed out that the fiow of current through the coil 212, in the manner above explained, serves to shift the bank of relay armatures l23a, b, and c toward the left in Figs. 3a and 3b, thereby conditioning the system for the transmission of signals identified with figures rather than letters.

Now upon the completion of the cycle, i. e., half revolution of the shaft i2! identified with the figure shift designation on the control tape, let it be assumed, in accordance with Fig. 5, that the next character to be printed is the Figure 5. This will mean that during the half revolution of the shaft 927, the tape will have been shifted to a position in which an opening is provided in line with the feeler pin H2 and the feeler pins will have been released to permit the feeler pin M2 to pass through the opening. As the bump I12 on the printer shaft cam disc l3l shifts the arm I33 toward the left upon the completion of the figure shift cycle of the timing shaft I21, the pawl it?) will be retracted from the ratchet H58 in the manner previously set forth and the brush arms will be permitted to sweep across the commutator segments until the brush associated with the commutator 1M reaches the segment 218 identified with the character 5. At this point a circuit will be completed from the negative side 15! of the current source, through the relay armature I2 I, line 2 ll, armature lZllb, line 2 l 8, armature l 19d, armature l Ith, and armature H119 to the contact 219, which, it will be understood, is connected with the segment 218 of the commutator. From the latter the circuit is completed through the collector ring section 2.88 and the line 225, branch line 226, contact 22?, armature l23a, and line I59 to the positive side E5!) of the current source. In shifting from the segment 253 of the commutator Hit to the segment 273, the brush identified with commutator I02 will be carried over a series of the segments of this commutator to the segment 285 and then to the insulating space 282 just beyond segment 28L This, as indicated in Fig. 5, results in the transmission over the lines I46 of a series of positive and negative pulses concluding with a negative pulse 283 just prior to the open signal predetermined by the insulating section 282 of the commutator H52. As previously explained in connection with the transmission of the character W and the printing of the latter, a long open printing signal will be sent over the lines hit at this time, the length of this being indicated by the section 236 of the current flow line of Fig. 5. As in the case of the transmission of the character W, the completion of the long open printing signal will be followed by a restoration of the negative signal over the lines I48, as indicated by the section 285 of the current flow line in Fig. 5.

Now assuming that the next character to be 2d printed is another figure 5, the new position of the tape will have an opening in the line with the feeler pin H2 so that the circuit through the fan bank will be restored immediately upon the re-' lease of the feeler pins by the magnet ififi. Accordingly, as in the case of the figure shift signal, the pawl I09 will not be retracted upon the completion of the cycle of the print timing shaft 121 so that no shifting of the brush will take place. fact that the armature lfii] will be drawn toward the left as soon as the circuit through the coil I95. is broken by the coaction of the bump on the disc I32 with the arm 34. This will occur before a circuit could be completed from the negative side ill of the current source, through the line Ht, armature L59, line I53 and coil 5% to the positive side Hill of the current source; Accordingly, the effect of selecting the same character for printing again is simply to retract the detent pawl 28 and to permit another half revoultion of the print timing shaft l2'i" with the various functions incident to its operation.

From time to time it is desirable to transmit a unison signal for the purpose of insuring that all of the outlying printers are in unison with the transmitter. This is set forth in some detail in the Ackell et al. Patent No. 2,017,087 above mentioned. Substantially the same arrangement may be provided in connection with the new control system. Briefly, the arrangement may be such that when the unison signal is to be sent out, the portion of the tape presented at the analyzer pins will have no holes therethrough so that the armatures of all the relays of the fan bank will be held toward the left. This will carry the current from the negative side [55 of the current source to the point 286 which is not connected with any segment on the commutator ltd and, therefore, the circuit through the fan bank cannot be completed. Accordingly, when the ratchet N38 is released upon the retraction of the pawl I09 at the completion of the preceding printing cycle of the shaft E21, the brush arms m5 and H36 will be permitted to rotate continuously until arrested by the special means disclosed in the above mentioned patent. This involves a worm and a follower which is permitted to travel along the worm unless and until it is shifted out of the latter, which occurs upon each release of the timing shaft I21. Therefore, in the ordinary operation of the system, the follower does not travel far enough to have an effect upon the system. However, when the unison signal is predetermined by the tape, the follower is permitted to travel until it brings about the actuation of a switch diagrammatically illustrated at 2M in Fig. 3a. When this switch is closed, a circuit from the source i5! is carried to the space segment 238 of the commutator its and the brush arm I will, therefore, be arrested when the associated brush reaches this segment during the subsequent revolution. This, in the preferred construction, will ordinarily be on the 5th revolution of the brush arms. The control of the printing operation then takes place in the same manner as if the spaced character had been expressly predetermined by the tape. It will be understood, however, that the selection of the space position of the printing wheels at the several printers will be brought about by the arrangement disclosed in the abovementioned Ackell and Paulding patent. Briefly, this may involve stopping the printing Wheel shaft, by a positive stop finger or the like, in a predetermined This, it will be understood, is due to the position in which the space portion of the wheel is opposite the platen, after the printing wheel has been permitted to rotate about three complete revolutions.

Provision is made for temporarily arresting the operation of the transmitter when the tape available for analysis by the analyzer i i i becomes less than a predetermined minimum, i. e., when it is being analyzed at a more rapid rate than it is being supplied from the punching machine or machines. For this purpose an arm (not shown), which cooperates with the tape at a point just in advance of that at which it is analyzed by the pins of the analyzer H i, is operated by the tape, when the latter becomes relatively taut, and is shifted to a position in which it opens a circuit at the point 289 in Fig. 3b. This serves to break the circuit which normally extends from the positive side Hi l of a current source through the switch 285, line 299, and magnet coil 295 to the negative side 292 of the current source. Normally the current thus flowing serves to hold a detent arm or pawl 283 in the raised position indicated in Fig. 3b, out of the path of the projections 29:! on a disc 295 secured to the print timing shaft I21. When the current is broken by the operation of the switch 289, as explained, the arm 293 is released and serves to arrest the disc 295 on the next print timing cycle of the shaft I2? in a position about 30 removed from the normal completion of the print timing cycle. This is such that the projection 298 on the cam I32 is in engagement with the arm 534, thus completing the circuit, hereinabove described, through the relay coil 2 it and thereby serving to draw the armature 2i2 toward the left. This, as previously explained, completes a circuit from the negative side 28'! of the power source through the armature 212, line 2M, and coil 2G2 to the positive side 20! of the current source and insures the maintenance of the armature M9 in the closed circuit position indicated in Fig. 31 Accordingly, during the period in which the transmitter is held out of operation by the engagement of pawl 293 with one of the lugs 2%, the last signal sent out over the lines 146 will be sustained. When additional tape is supplied to the analyzer, the switch 239 is again closed and the pawl 293 is retracted to permit completion of the unfinished cycle of the print timing shaft I21. The operation of the system, which is thus resumed, is the same as if it had not been interrupted.

Provision is made for transmitting over the lines 145 a relatively long open signal which is substantially longer than the open signal which brings about the carriage return and may be in the neighborhood of seconds. This is adapted for the ringing of a bell at each of the printers connected with the lines Mt. When such a bell signal is to be transmitted a figure shift must first take place, in the manner hereinabove described, and this is then followed by a series of holes in the tape corresponding with the letter S, these holes being aligned with the pins H4 and I Hi. It should be borne in mind that the feeding of the tape and the release of the feeler pins to cooperate with the new openings in the tape occurs during an early portion of the cycle of the print timing shaft 82? identified with the preceding character determined by the tape. This preceding signal may have been associated with a figure, or with the figure shift if letters were being transmitted immediately prior to the bell ringing signal. Immediately upon the new positioning of the pins of the analyzer, a circuit will be completed through the fan bank Without movement of the brush arms it?) and tilt, i. e., this circuit is'completed regardless of the posi tion of the brush arms. It may be traced as follows: from the negative side lfil of the power source, through the coil i52, armature l2i, line E53, armature l2i3a, armature H91), armature H80, and armature Ill), to the contact 23!. From this contact the circuit continues through line 239, coil 229, coil 228, line contact 22?, thence through the relay armature i23c, which will have been shifted toward the left by the figure shift signal, and then through line iii} to the positive side ice of the current source. Completion of the circuit in this manner through the coil 2239 will draw the armature 263d toward the right and thus open the circuit from the negative side 2M of the current source, through armature 2%, line 235, etc. to the positive side 2M of the current source. At this time the parallel circuit connecting the points MM and it? through the lines 2 is and 72 I3 and armature 222 will be closed. However, this parallel circuit will be opened upon the completion of the preceding cycle of the print timing shaft lZ'i, because of the swinging of the arm its to the left and the completion of a circuit from the negative side ll! of the current source through line ill armature 58%, line 25!, armature 2&2 (which will be in its lefthand position), line 2 33, and coil 2% to the positive side 245 of the current source. In thus energizing the coil 2%, the armature 2E2 will be swung toward the right to open the parallel circuit mentioned. This will result in the release of the armature use by the coil 282 and will initiate an open signal which will be transmitted over the lines it.

It should be noted at this point that the circuit, which is normally completed upon the shifting of the arm I33 toward the left, on the completion of a circuit through the fan bank, to bring about the retraction of the detent pawl I23 of the print timing mechanism, will be broken so that the print timing shaft i2l will not be released. This is due to the passage of the current, as explained above, through the coil 228 which causes armature iii! to be shifted toward the right. It will be recalled that the circuit which normally brings about operation of the pawl I28 extends from the negative side ii! of the current source through line llil, armature 169, line H3, line ll i, armature 1'55, lines H6 and ill, coils I78 and H9, line ice, and armature is! to the positive side i872 of the current source. Breaking of this circuit by the shifting of armature 58! toward the right also prevents energization of the coil H9 and, therefore, leaves the armature E88 toward the right, as it was last shifted, and thus prevents operation of the magnet I50 to retract the analyzer pins. Shifting of the armature I toward the right establishes a new circuit from the positive side i532 of the current source through a line 296 and a heater coil 29'! to the negative side 2% of the current source. Coil 23'! is associated with a thermal switch 299 of any suitable construction adapted to be operated when bi-metallic elements or the'like are raised to a predetermined temperature. For the present purposes the construction is preferably such that it will require about 3 seconds of the passage of the current through the heating coil 29? to bring about the operation of the switch. When the switch is finally operated, contact is made between the point 363 on 

